#ifndef _LIST_H_
#define _LIST_H_
 
 
#if defined(_LINUX_GCC_)
#define INLINE  inline
#else
#define INLINE  __inline
#endif
 

#ifdef __cplusplus
extern "C" {
#endif


 /*
  * Simple doubly linked list implementation.
  *
  * Some of the internal functions ("__xxx") are useful when
  * manipulating whole lists rather than single entries, as
  * sometimes we already know the next/prev entries and we can
  * generate better code by using them directly rather than
  * using the generic single-entry routines.
  */
 
 struct list_head {
	 struct list_head *next, *prev;
 };
 
#define LIST_HEAD_INIT(name) { &(name), &(name) }
 
#define LIST_HEAD(name) \
	 struct list_head name = LIST_HEAD_INIT(name)
 
 static INLINE void INIT_LIST_HEAD(struct list_head *list)
 {
	 list->next = list;
	 list->prev = list;
 }
 /*
  * Insert a new entry between two known consecutive entries.
  *
  * This is only for internal list manipulation where we know
  * the prev/next entries already!
  */
 static INLINE void __list_add(struct list_head *new,
				   struct list_head *prev,
				   struct list_head *next)
 {
	 next->prev = new;
	 new->next = next;
	 new->prev = prev;
	 prev->next = new;
 }
 
 /**
  * list_add - add a new entry
  * @new: new entry to be added
  * @head: list head to add it after
  *
  * Insert a new entry after the specified head.
  * This is good for implementing stacks.
  */
 static INLINE void list_add(struct list_head *new, struct list_head *head)
 {
	 __list_add(new, head, head->next);
 }
 
 
 /**
  * list_add_tail - add a new entry
  * @new: new entry to be added
  * @head: list head to add it before
  *
  * Insert a new entry before the specified head.
  * This is useful for implementing queues.
  */
 static INLINE void list_add_tail(struct list_head *new, struct list_head *head)
 {
	 __list_add(new, head->prev, head);
 }
 
 /*
  * Delete a list entry by making the prev/next entries
  * point to each other.
  *
  * This is only for internal list manipulation where we know
  * the prev/next entries already!
  */
 static INLINE void __list_del(struct list_head * prev, struct list_head * next)
 {
	 next->prev = prev;
	 prev->next = next;
 }
 
 /**
  * list_del - deletes entry from list.
  * @entry: the element to delete from the list.
  * Note: list_empty() on entry does not return true after this, the entry is
  * in an undefined state.
  */
 static INLINE void list_del(struct list_head *entry)
 {
	 __list_del(entry->prev, entry->next);
	 entry->next = NULL;
	 entry->prev = NULL;
 }

 
 static INLINE int list_is_del(struct list_head *entry)
 {
	 return (entry->next == NULL) && (entry->prev == entry->next);
 }

 
 /**
  * list_replace - replace old entry by new one
  * @old : the element to be replaced
  * @new : the new element to insert
  *
  * If @old was empty, it will be overwritten.
  */
 static INLINE void list_replace(struct list_head *old,
				 struct list_head *new)
 {
	 new->next = old->next;
	 new->next->prev = new;
	 new->prev = old->prev;
	 new->prev->next = new;
 }
 
 static INLINE void list_replace_init(struct list_head *old,
					 struct list_head *new)
 {
	 list_replace(old, new);
	 INIT_LIST_HEAD(old);
 }
 
 /**
  * list_del_init - deletes entry from list and reinitialize it.
  * @entry: the element to delete from the list.
  */
 static INLINE void list_del_init(struct list_head *entry)
 {
	 __list_del(entry->prev, entry->next);
	 INIT_LIST_HEAD(entry);
 }
 
 /**
  * list_move - delete from one list and add as another's head
  * @list: the entry to move
  * @head: the head that will precede our entry
  */
 static INLINE void list_move(struct list_head *list, struct list_head *head)
 {
	 __list_del(list->prev, list->next);
	 list_add(list, head);
 }
 
 /**
  * list_move_tail - delete from one list and add as another's tail
  * @list: the entry to move
  * @head: the head that will follow our entry
  */
 static INLINE void list_move_tail(struct list_head *list,
				   struct list_head *head)
 {
	 __list_del(list->prev, list->next);
	 list_add_tail(list, head);
 }
 
 /**
  * list_is_last - tests whether @list is the last entry in list @head
  * @list: the entry to test
  * @head: the head of the list
  */
 static INLINE int list_is_last(const struct list_head *list,
				 const struct list_head *head)
 {
	 return list->next == head;
 }
 
 /**
  * list_empty - tests whether a list is empty
  * @head: the list to test.
  */
 static INLINE int list_empty(const struct list_head *head)
 {
	 return head->next == head;
 }

 /**
  * list_empty_careful - tests whether a list is empty and not being modified
  * @head: the list to test
  *
  * Description:
  * tests whether a list is empty _and_ checks that no other CPU might be
  * in the process of modifying either member (next or prev)
  *
  * NOTE: using list_empty_careful() without synchronization
  * can only be safe if the only activity that can happen
  * to the list entry is list_del_init(). Eg. it cannot be used
  * if another CPU could re-list_add() it.
  */
 static INLINE int list_empty_careful(const struct list_head *head)
 {
	 struct list_head *next = head->next;
	 return (next == head) && (next == head->prev);
 }
 
 /**
  * list_is_singular - tests whether a list has just one entry.
  * @head: the list to test.
  */
 static INLINE int list_is_singular(const struct list_head *head)
 {
	 return !list_empty(head) && (head->next == head->prev);
 }
 
 static INLINE void __list_cut_position(struct list_head *list,
		 struct list_head *head, struct list_head *entry)
 {
	 struct list_head *new_first = entry->next;
	 list->next = head->next;
	 list->next->prev = list;
	 list->prev = entry;
	 entry->next = list;
	 head->next = new_first;
	 new_first->prev = head;
 }
 
 /**
  * list_cut_position - cut a list into two
  * @list: a new list to add all removed entries
  * @head: a list with entries
  * @entry: an entry within head, could be the head itself
  *  and if so we won't cut the list
  *
  * This helper moves the initial part of @head, up to and
  * including @entry, from @head to @list. You should
  * pass on @entry an element you know is on @head. @list
  * should be an empty list or a list you do not care about
  * losing its data.
  *
  */
 static INLINE void list_cut_position(struct list_head *list,
		 struct list_head *head, struct list_head *entry)
 {
	 if (list_empty(head))
		 return;
	 if (list_is_singular(head) &&
		 (head->next != entry && head != entry))
		 return;
	 if (entry == head)
		 INIT_LIST_HEAD(list);
	 else
		 __list_cut_position(list, head, entry);
 }
 
 static INLINE void __list_splice(const struct list_head *list,
				  struct list_head *prev,
				  struct list_head *next)
 {
	 struct list_head *first = list->next;
	 struct list_head *last = list->prev;
 
	 first->prev = prev;
	 prev->next = first;
 
	 last->next = next;
	 next->prev = last;
 }
 
 /**
  * list_splice - join two lists, this is designed for stacks
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  */
 static INLINE void list_splice(const struct list_head *list,
				 struct list_head *head)
 {
	 if (!list_empty(list))
		 __list_splice(list, head, head->next);
 }
 
 /**
  * list_splice_tail - join two lists, each list being a queue
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  */
 static INLINE void list_splice_tail(struct list_head *list,
				 struct list_head *head)
 {
	 if (!list_empty(list))
		 __list_splice(list, head->prev, head);
 }
 
 /**
  * list_splice_init - join two lists and reinitialise the emptied list.
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  *
  * The list at @list is reinitialised
  */
 static INLINE void list_splice_init(struct list_head *list,
					 struct list_head *head)
 {
	 if (!list_empty(list)) {
		 __list_splice(list, head, head->next);
		 INIT_LIST_HEAD(list);
	 }
 }
 
 /**
  * list_splice_tail_init - join two lists and reinitialise the emptied list
  * @list: the new list to add.
  * @head: the place to add it in the first list.
  *
  * Each of the lists is a queue.
  * The list at @list is reinitialised
  */
 static INLINE void list_splice_tail_init(struct list_head *list,
					  struct list_head *head)
 {
	 if (!list_empty(list)) {
		 __list_splice(list, head->prev, head);
		 INIT_LIST_HEAD(list);
	 }
 }
 
  /**
  * container_of - cast a member of a structure out to the containing structure
  * @ptr:	  the pointer to the member.
  * @type:	   the type of the container struct this is embedded in.
  * @member:	 the name of the member within the struct.
  *
  */
#ifdef _LINUX_GCC_
#define container_of(ptr, type, member) ({            \
			  const typeof( ((type *)0)->member ) *__mptr = (ptr);	  \
			  (type *)( (char *)__mptr - offsetof(type,member) );})
#else
#define offsetof(TYPE, MEMBER) ((unsigned int) &((TYPE *)0)->MEMBER)
#define container_of(ptr, type, member) ((type *)( (char *)( ptr ) - offsetof(type,member)))
#endif
 
 
 /**
  * list_entry - get the struct for this entry
  * @ptr:	 the &struct list_head pointer.
  * @type:	 the type of the struct this is embedded in.
  * @member: the name of the list_struct within the struct.
  */
#define list_entry(ptr, type, member) \
	 container_of(ptr, type, member)
 
 /**
  * list_first_entry - get the first element from a list
  * @ptr:	 the list head to take the element from.
  * @type:	 the type of the struct this is embedded in.
  * @member: the name of the list_struct within the struct.
  *
  * Note, that list is expected to be not empty.
  */
#define list_first_entry(ptr, type, member) \
	 list_entry((ptr)->next, type, member)


 /**
  * list_last_entry - get the last element from a list
  * @head:	 the list head to take the element from.
  * @type:	 the type of the struct this is embedded in.
  * @member: the name of the list_struct within the struct.
  *
  * Note, that list is expected to be not empty.
  */
#define list_last_entry(head, type, member) \
	 list_entry((head)->prev, type, member)

 /**
  * list_for_each	 -	 iterate over a list
  * @pos:	 the &struct list_head to use as a loop cursor.
  * @head:	 the head for your list.
  */
#define list_for_each(pos, head) \
	 for (pos = (head)->next;  pos != (head); \
			 pos = pos->next)
 
 /**
  * __list_for_each  -	 iterate over a list
  * @pos:	 the &struct list_head to use as a loop cursor.
  * @head:	 the head for your list.
  *
  * This variant differs from list_for_each() in that it's the
  * simplest possible list iteration code, no prefetching is done.
  * Use this for code that knows the list to be very short (empty
  * or 1 entry) most of the time.
  */
#define __list_for_each(pos, head) \
	 for (pos = (head)->next; pos != (head); pos = pos->next)
 
 /**
  * list_for_each_prev	 -	 iterate over a list backwards
  * @pos:	 the &struct list_head to use as a loop cursor.
  * @head:	 the head for your list.
  */
#define list_for_each_prev(pos, head) \
	 for (pos = (head)->prev; pos != (head); \
			 pos = pos->prev)
 
 /**
  * list_for_each_safe - iterate over a list safe against removal of list entry
  * @pos:	 the &struct list_head to use as a loop cursor.
  * @n: 	 another &struct list_head to use as temporary storage
  * @head:	 the head for your list.
  */
#define list_for_each_safe(pos, n, head) \
	 for (pos = (head)->next, n = pos->next; pos != (head); \
		 pos = n, n = pos->next)
 
 /**
  * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
  * @pos:	 the &struct list_head to use as a loop cursor.
  * @n: 	 another &struct list_head to use as temporary storage
  * @head:	 the head for your list.
  */
#define list_for_each_prev_safe(pos, n, head) \
	 for (pos = (head)->prev, n = pos->prev; \
				  pos != (head); \
		  pos = n, n = pos->prev)
 
 /**
  * list_for_each_entry  -	 iterate over list of given type
  * @pos:	 the type * to use as a loop cursor.
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  */
#define list_for_each_entry(pos, head, member)				\
	 for (pos = list_entry((head)->next, typeof(*pos), member);  \
		  &pos->member != (head);	 \
		  pos = list_entry(pos->member.next, typeof(*pos), member))
 
 /**
  * list_for_each_entry_reverse - iterate backwards over list of given type.
  * @pos:	 the type * to use as a loop cursor.
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  */
#define list_for_each_entry_reverse(pos, head, member)			\
	 for (pos = list_entry((head)->prev, typeof(*pos), member);  \
		   &pos->member != (head);	 \
		  pos = list_entry(pos->member.prev, typeof(*pos), member))
 
 /**
  * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
  * @pos:	 the type * to use as a start point
  * @head:	 the head of the list
  * @member: the name of the list_struct within the struct.
  *
  * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
  */
#define list_prepare_entry(pos, head, member) \
	 ((pos) ? : list_entry(head, typeof(*pos), member))
 
 /**
  * list_for_each_entry_continue - continue iteration over list of given type
  * @pos:	 the type * to use as a loop cursor.
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Continue to iterate over list of given type, continuing after
  * the current position.
  */
#define list_for_each_entry_continue(pos, head, member) 		\
	 for (pos = list_entry(pos->member.next, typeof(*pos), member);  \
		   &pos->member != (head);	 \
		  pos = list_entry(pos->member.next, typeof(*pos), member))
 
 /**
  * list_for_each_entry_continue_reverse - iterate backwards from the given point
  * @pos:	 the type * to use as a loop cursor.
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Start to iterate over list of given type backwards, continuing after
  * the current position.
  */
#define list_for_each_entry_continue_reverse(pos, head, member)		\
	 for (pos = list_entry(pos->member.prev, typeof(*pos), member);  \
		  &pos->member != (head);	 \
		  pos = list_entry(pos->member.prev, typeof(*pos), member))
 
 /**
  * list_for_each_entry_from - iterate over list of given type from the current point
  * @pos:	 the type * to use as a loop cursor.
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Iterate over list of given type, continuing from current position.
  */
#define list_for_each_entry_from(pos, head, member) 			\
	 for (;  &pos->member != (head); \
		  pos = list_entry(pos->member.next, typeof(*pos), member))
 
 /**
  * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
  * @pos:	 the type * to use as a loop cursor.
  * @n: 	 another type * to use as temporary storage
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  */
#define list_for_each_entry_safe(pos, n, head, member)			\
	 for (pos = list_entry((head)->next, typeof(*pos), member),  \
		 n = list_entry(pos->member.next, typeof(*pos), member); \
		  &pos->member != (head);					 \
		  pos = n, n = list_entry(n->member.next, typeof(*n), member))
 
 /**
  * list_for_each_entry_safe_continue
  * @pos:	 the type * to use as a loop cursor.
  * @n: 	 another type * to use as temporary storage
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Iterate over list of given type, continuing after current point,
  * safe against removal of list entry.
  */
#define list_for_each_entry_safe_continue(pos, n, head, member) 		\
	 for (pos = list_entry(pos->member.next, typeof(*pos), member), 	 \
		 n = list_entry(pos->member.next, typeof(*pos), member);	 \
		  &pos->member != (head);						 \
		  pos = n, n = list_entry(n->member.next, typeof(*n), member))
 
 /**
  * list_for_each_entry_safe_from
  * @pos:	 the type * to use as a loop cursor.
  * @n: 	 another type * to use as temporary storage
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Iterate over list of given type from current point, safe against
  * removal of list entry.
  */
#define list_for_each_entry_safe_from(pos, n, head, member) 			\
	 for (n = list_entry(pos->member.next, typeof(*pos), member);		 \
		  &pos->member != (head);						 \
		  pos = n, n = list_entry(n->member.next, typeof(*n), member))
 
 /**
  * list_for_each_entry_safe_reverse
  * @pos:	 the type * to use as a loop cursor.
  * @n: 	 another type * to use as temporary storage
  * @head:	 the head for your list.
  * @member: the name of the list_struct within the struct.
  *
  * Iterate backwards over list of given type, safe against removal
  * of list entry.
  */
#define list_for_each_entry_safe_reverse(pos, n, head, member)		\
	 for (pos = list_entry((head)->prev, typeof(*pos), member),  \
		 n = list_entry(pos->member.prev, typeof(*pos), member); \
		  &pos->member != (head);					 \
		  pos = n, n = list_entry(n->member.prev, typeof(*n), member))


	 
#ifdef __cplusplus
}
#endif
#endif  //_LINUX_LIST_H
 
 
